NAME

       NetPacket - assemble/disassemble network packets at the protocol level

VERSION

       version 1.7.2

SYNOPSIS

           # NetPacket is a base class only

DESCRIPTION

       "NetPacket" provides a base class for a cluster of modules related to decoding and
       encoding of network protocols.  Each "NetPacket" descendent module knows how to encode and
       decode packets for the network protocol it implements.  Consult the documentation for the
       module in question for protocol-specific implementation.

       Note that there is no inheritance in the "NetPacket::" cluster of modules other than each
       protocol module being a "NetPacket".  This was seen to be too restrictive as imposing
       inheritance relationships (for example between the IP, UDP and TCP protocols) would make
       things like tunneling or other unusual situations difficult.

WRITING YOUR OWN "NetPacket::" MODULE

       You are encouraged to write additional "NetPacket::" modules as well as improve existing
       ones.  Contact the maintainer of the module in question with your suggestions or changes.

       The following sections are a list of suggestions and conventions for writing a
       "NetPacket::" module.

   Naming Conventions
       When creating a module in the "NetPacket::" namespace, it is suggested that you stick to a
       couple of conventions when naming packet contents.  This will hopefully lead to a
       consistent namespace making the "NetPacket::" easier to use.

       Content names are all lowercase, with underscores separating multiple words.  The
       following abbreviations are recommended:

                   Word                Abbreviation
                   --------------------------------
                   source              src
                   destination         dest
                   checksum            cksum
                   identifier          id
                   version             ver
                   protocol            proto

   Required Methods
       encode(), decode(), strip()

   Required Fields
       Every NetPacket:: object should have the following fields.

       _parent
           A link to the parent "NetPacket::" object in which this "NetPacket::" object is
           encaulated.  This field is undefined if there is no parent object.

       _frame
           A copy of the raw data of the packet.

       data
           This field should contain the data encapsulated in the packet (i.e any headers or
           trailers stripped off) or undef if the packet contains no data.  Note that in this
           sense, "data" is taken to mean information not relevant to the particular protocol
           being decoded.  For example, an ARP packet contains many header fields but no data.  A
           UDP datagram, however contains header fields and a payload.

SEE ALSO

       Joel Knight has a patch for NetPacket for IPv6 support available at
       http://www.packetmischief.ca/code/netpacket/.

COPYRIGHT AND LICENSE

       Copyright (c) 2001 Tim Potter and Stephanie Wehner.

       Copyright (c) 1995,1996,1997,1998,1999 ANU and CSIRO on behalf of the participants in the
       CRC for Advanced Computational Systems ('ACSys').

       This module is free software.  You can redistribute it and/or modify it under the terms of
       the Artistic License 2.0.

       This program is distributed in the hope that it will be useful, but without any warranty;
       without even the implied warranty of merchantability or fitness for a particular purpose.

AUTHORS

       Tim Potter <tpot@samba.org>

       Stephanie Wehner <atrak@itsx.com>

       Yanick Champoux <yanick@cpan.org>